THE 


MENTAL  SYMPTOMS 


OF 

FATIGUE 


By  EDWARD  COWLES,  M.D. 
Medical  Superintendent  of  the  McLean  Hospital 
SOMERVILLE ,  MASS. 


Reprinted  from  the  Transactions  of  the  New  York  State  Medical  Association 


New  York 

FLESS  &  RIDGE  PRINTING  CO. 

Fifth  Aye.  and  16th  St. 

1893 


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I 


ise 

C.«3>yy> 


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THE  MENTAL  SYMPTOMS  OF  FATIGUE.1 


The  subject  of  mental  symptoms  carries  with  it  the 
suggestion  of  something  vague  and  difficult  of  appre¬ 
hension.  The  study  of  mental  disorders  is  forbidding  to 
the  general  physician  who  feels  that  he  has  neither  time 
nor  patience  for  it.  The  present  purpose  is  to  contribute 
something  to  a  better  understanding  and  an  easier  ap¬ 
preciation  of  the  mental  symptoms  of  fatigue,  which  will 
be  considered  under  the  following  heads  :  (1)  the  nature 
of  mental  symptoms ;  (2)  the  physical  conditions  of 
fatigue  ;  (3)  some  elementary  facts  of  the  nervous  and 
mental  mechanism  ;  and  (4)  the  alterations  of  mental 
functions  that  are  significant  as  symptoms. 


1.  THE  NATURE  OF  MENTAL  SYMPTOMS. 


1 


It  lias  been  the  fashion  to  regard  this  branch  of  neu¬ 
rology  as  being  slow  in  its  progress,  having  no  coherent 
principles,  resting  upon  an  indeterminate  basis,  and  as 
being  unscientific  in  its  classification  and  therapeutics. 
Krafft-Ebing  admits  that  the  anatomy  of  the  nervous 
system  has  so  far  been  incomplete  and  unsatisfactory  in 
not  enabling  us  to  reason  from  structure  to  function,  as 
has  been  done  in  the  relatively  simple  structure  of  the 
vegetative  organs ;  and  that  pathology  has  been  disap¬ 
pointing  in  failing  to  explain  the  most  marked  disturb¬ 
ances  of  function.  But  he  points  to  the  fact  that 
psychiatry  is  one  of  the  youngest  of  our  special  sci¬ 
ences.  He  says  it  seems  almost  exclusively  dependent 


w 


1  Read  before  the  New  York  State  Medical  Association,  November  1G, 
1892. 


2 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


on  itself,  and  is  limited  to  the  direct  observation  of  mor¬ 
bid  mental  phenomena  ;  also  that  it  is  from  the  empirical 
valuation  of  these  phenomena  that  we  are  obliged  to 
draw  conclusions  as  to  the  kind  and  degree  of  the  func¬ 
tional  disturbance  in  the  organ  of  mind.  His  conclusion 
is  that  great  progress  has  been  made  in  the  raising  of 
psychiatry  to  the  rank  of  a  natural  science  with  methods 
of  empirical  research.  Its  direct  advancement  can  be 
accomplished  only  by  tireless  observation  and  report  of 
clinical  phenomena,  and  thus  fixing  the  facts  of  the 
mental  life.  While  mental  disease  is  always  brain  dis¬ 
ease,  the  course  of  the  processes  in  mental  disorders  is 
discovered  through  observation,  as  in  any  other  disease. 

The  hope  of  gaining  a  clearer  appreciation  of  mental 
symptoms  lies  in  the  fact  that  we  may  observe  so  much 
more  directly  the  manifestations  of  mind,  and  conse¬ 
quently  of  nervous  function,  than  we  can  those  of  any 
other  function  of  the  nervous  system.  We  may  study, 
by  the  aid  of  anatomy,  physiology,  pathology,  and 
physics,  an  involuntary  mechanism  like  the  heart ;  or 
the  action  of  the  muscular  system  as  a  voluntary  mech¬ 
anism.  In  the  action  of  the  peripheral  apparatus  we 
note  the  expression  of  the  setting  free  of  central  nervous 
energy,  and  can  trace  the  conducting  path  of  the  motive 
energy  back  to  motor  centres.  But  we  can  get  no  further 
than  to  speak  of  4  4  innervation  ’ 5  and  4  4  inhibition  ’  ’  with 
entire  ignorance  of  the  way  in  which  nervous  substance 
is  stimulated,  and  augments  or  controls  that  which 
stimulates  it  into  activity.  We  are  conscious  that  the 
mode  of  expression  of  the  active  mind  through  the 
peripheral  instruments  is  indirect. 

All  this  is  true  also  of  the  complex  organ  of  speech, 
when  examined  as  an  organ,  and  as  one  of  the  minor 
mechanisms  of  whose  anatomy  and  pathology  we  may 
make  the  most  scientific  study,  as  we  need  to  do  for  a 
correct  interpretation  of  any  change  from  normal  action. 
But  through  this  organ  we  hear  in  the  articulate  sounds 
with  varied  tone,  pitch,  and  inflection,  and  in  the  words 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


3 


which  this  instrument  produces,  the  direct  expression  of 
a  function  by  which  brain  cells  are  able  to  convey  to  our 
understanding  the  largeness  and  fineness  of  meaning 
that  is  comprehended  in  the  “infinite  variety”  of  the 
human  mind.  This  takes  us  into  a  field  of  phenomena 
that  our  kindred  sciences  fail  to  reach.  Instead  of 
lamenting  that  they  do  not  aid  us,  it  is  perhaps  more 
true  to  say  that  we  do  not  need  their  aid  in  the  interpre¬ 
tation  of  these  manifestations,  which,  by  a  superior  mode 
of  expression,  convey  finer  variations  of  meaning,  and 
make  revelations  of  earlier  and  slighter  departures  from 
normal  action  than  we  can  get  from  any  other  function 
of  the  human  organism.  Moreover,  it  is  given  us  to 
make  these  discriminations  by  the  natural  law  of  mind, 
without  any  need  of  laborious  study  and  interpretation 
of  the  working  of  an  intervening  instrument.  We  hear 
the  expression  of  thought  and  feeling  in  sounds  that  we 
come  to  know,  and  we  need  not  stop  to  note  the  mech¬ 
anism  of  their  utterance.  From  the  moment  when  we 
are  thrust  into  this  noisy  world,  the  articulate  sounds  of 
the  human  voice  begin  to  be  familiar  to  us.  Every  man 
makes  his  way  in  the  world  largely  by  his  success  in 
measuring  the  minds  of  his  fellow-men.  We  have,  by 
nature,  a  most  intimate  common  knowledge  of  variations 
in  mental  function  ;  of  no  science  have  we  a  more  prac¬ 
tical  every-day  knowledge  than  of  psychology.  It  is 
true  that  we  have  to  discover  a  way  to  reduce  the  data 
of  this  knowledge  to  orderly  form,  and  to  recognise  the 
import  of  commonly  observed  mental  manifestations  by 
observing  their  correspondence  with  recognised  bodily 
conditions.  This  must  constitute  a  true  science  of  the 
health  and  disease  of  a  function  which  has  its  own 
peculiar  character  and  physiological  laws. 

The  nature  of  mental  symptoms,  or  manifestations  of 
departures  from  normal  functions,  being  thus  under¬ 
stood,  we  should  approach  their  study  with  minds  free 
from  prejudice,  prepared  to  observe  and  fix  the  facts  of 
each  kind  of  manifestation  and  array  them  in  the  order 


4  THE  MENTAL  SYMPTOMS  OF  FATIGUE. 

of  their  occurrence  and  relations  with  each  other.  The 
question  now  comes,  can  we  set  up  a  plain  and  intelli¬ 
gible  conception  of  the  normal  mental  mechanism  that 
will  serve  as  our  standard  in  which  to  note  and  localise, 
as  it  were,  the  departures  from  normal  action?  We 
must  begin  in  an  elementary  way,  and  deal  first  with 
the  slighter  variations  from  conditions  of  health  in  the 
mechanism,  and  its  fullness  of  power  to  do  what  it  can 
do.  In  the  brief  time  allotted  here,  the  attempt  will  be 
made  to  do  little  more  than  to  point  out  a  method  of 
observation  and  study  on  the  basis  of  some  of  the  prim¬ 
ary  facts  of  the  mental  and  nervous  mechanism. 

2.  THE  PHYSICAL  CONDITIONS  OF  FATIGUE. 

The  proposition  may  be  laid  down  to  start  with,  as  a 
working  formula,  that  the  organ  of  the  mind  is  an  appar¬ 
atus  for  the  storage  and  discharge  of  nervous  energy, 
and  that  all  mental  symptoms  indicate  a  failure  of  the 

mental  elements  to  functionate  with  normal  co-ordi- 

/ 

nation,  because  of  modification  of  the  power  to  set  free 
nervous  energy,  due  to  lack  of  the  discharging  force,  or 
the  obstruction  of  it,  or  to  lessened  power  of  control ;  or 
as  due  to  excess  of  stimulation  and  discharge,  which 
means  also  relative  weakness  of  inhibitory  control.  All 
of  these  conditions  of  nervous  action  may  exist  together, 
or  side  by  side,  and  often  do,  not  only  in  the  most  mani¬ 
fest  of  mental  diseases,  but  in  the  lesser  degree  of  ner¬ 
vous  fatigue.  In  fact  the  key  to  the  understanding  of 
these  graver  conditions  seems  to  be  in  the  appreciation  of 
the  slighter  degree  of  nervous  exhaustion  always  to  be 
observed  in  normal  fatigue.  The  condition  of  the  cen¬ 
tral  organ  may  be  directly  observed  through  the  mental 
symptoms  which  quickly  reflect  the  variations  in  nervous 
force  and  activity.  The  correct  understanding  of  these 
symptoms  is  essential  to  the  best  treatment  of  nervous 
exhaustion  in  all  its  forms.  And  this  is  the  soil  in  which 
the  more  serious  nervous  diseases  take  root  and  grow. 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


5 


The  bodily  conditions  of  fatigue  should  first  be  con¬ 
sidered  as  far  as  we  can  know  them,  and  may  be  studied 
in  their  two  forms  of  degrees  :  (1)  normal  fatigue ,  or  th 
condition  of  wholesome  tire  from  daily  physiological 
use  ;  and  (2)  pathological  fatigue ,  or  the  condition  of 
persistent  “  impoverishment  of  nervous  tissue  in  excess 
of  repair,”  according  to  Beard,  which  constitutes  nervous 
exhaustion  or  neurasthenia.  The  mental  symptoms  are 
to  be  studied  in  their  close  and  direct  correspondence 
with  these  conditions  of  fatigue. 

The  effects  of  fatigue  are  produced  by  sufficiently  con¬ 
tinued  exercise  in  the  physiological  use  of  any  func¬ 
tion,  muscular  or  nervous.  The  sense  of  fatigue  is  com¬ 
plex,  and  may  have  a  central  or  peripheral  source,  or 
both  together.  In  muscular  tissue  the  condition  of 
fatigue  depends  upon  the  physiological  fact  that  muscu¬ 
lar  contraction  is  in  some  way  or  other  the  result  of  a 
chemical  change,  whereby  the  latent  energy  is  set  free 
and  expended  in  the  mechanical  work,  with  also  the 
setting  free  of  heat.  The  resultant  chemical  products 
are  toxic,  and  obstructive  of  muscular  function  unless 
they  are  duly  washed  away  in  the  blood  current ;  and 
time  must  be  given  in  rest  and  sleep  for  this  process,  as 
well  as  for  nutrition  and  repair.  These  toxic  products 
being  variously  irritant  or  benumbing,  doubtless  thus 
affect  the  sensory  apparatus  through  which  fatigue  is 
felt.  It  is  evident  from  this  that  the  condition  of  mus¬ 
cular  fatigue  has  always  a  dual  character — there  is  direct 
expenditure  of  energy,  requiring  repair,  and  a  toxic 
element  that  may  be  obstructive  of  function,  both  that  of 
discharging  energy  and  of  taking  up  nutrition. 

In  nervous  substance,  the  nature  of  nerve  force  being 
unknown,  the  effects  of  the  passage  of  a  nervous  impulse 
along  nerve-fibres  are  not  demonstrable  as  attended  by 
chemical  changes,  or  loss  of  normal  irritability  as  a 
manifestation  of  fatigue.1  But  in  the  central  nervous 
organs  it  is  found  that  their  function  is  dependent  on  an 

1  Bowditch,  Jour,  of  Phys.,  Yol.  6,  p.  133. 


6  THE  MENTAL  SYMPTOMS  OF  FATIGUE. 

adequate  supply  of  oxygen,  and  this  implies  that  “in 
nervous,  as  in  muscular  substance,  a  metabolism,  mainly 
of  an  oxidative  character,  is  the  real  cause  of  the  develop¬ 
ment  of  energy.”1  In  fact  we  do  not  doubt  that  toxic 
waste  products  attend  upon  central  nervous  activity,  and 
this  accords  with  the  biological  theory  that  all  function 
is  due  to  chemical  changes  taking  place  within  the 
organism,  and  thatjthe  functional  activity  of  a  specialised 
tissue  dex>ends  primarily  upon  the  changes  in  its  indivi¬ 
dual  cells.  The  dual  character  of  all  conditions  of  pri¬ 
mary  fatigue  is  evident,  as  is  also  the  importance  of 
recognising  the  effects  of  the  self-produced  poisonous 
substances  that  regularly  result  from  the  chemical 
changes  in  tissue  metabolism  within  the  body,  as  we  are 
taught  by  the  brilliant  revelations  of  modern  chemical 
physiology  and  pathology. 

Normal  fatigue  from  the  discharge  of  tissue  energy 
is  therefore  shown  to  be  inseparably  accompanied  by 
toxic  products  that  contribute  to  the  effects  of  fatigue. 
Pathological  fatigue  represents  a  further  development 
and  persistence  of  this  condition  in  the  organism.  Stimu¬ 
lation  too  soon  repeated,  without  giving  time  for  rest  and 
repair,  finds  nerve-cells  in  fatigued  areas  having  less 
power  to  act  because  of  inanition  from  deficient  rest  and 
nourishment ;  they  are  also  hindered  in  action  by  the 
incomplete  removal  of  the  toxic  products  of  previous 
action.  Then  assimilation  is  further  hindered,  first,  by 
the  lessened  nutritive  quality  of  the  blood  from  the 
presence  of  non -eliminated  toxic  materials  ;  and  sec¬ 
ondly  the  probable  toxic  weakening  of  the  cells’  power 
to  assimilate  the  nutrition  that  is  furnished  to  them. 
The  development  of  a  manifestly  morbid  condition  may 
be  very  slow  and  insidious,  or  more  rapid,  according  as 
the  balance  of  the  processes  of  constructive  and  regres¬ 
sive  metabolism  are  more  or  less  on  the  side  of  impover¬ 
ishment,  exhaustion,  and  weakness.  From  the  gradually 
failing  elimination,  the  local  inanition  may  become  more 

1  Foster,  Physiology,  5th  Eng.  Ed.,  1890,  pp.  914-918. 


TEE  MENTAL  SYMPTOMS  OF  FATIGUE. 


7 


general,  and  the  first  results  are  an  increased  excitability 
from  weakened  resistance  and  inhibition,  with  a  quick 
exhaustion  of  the  nervous  system  under  exercise.  These 
are  the  constant  characteristics  of  neurasthenia.  Thus, 
as  Kowalewsky  1  says,  “a  locally  limited  over-strain  of 
a  certain  part  of  the  nervous  system  may  lead  to  general 
exhaustion  and  neurasthenia.”  Hence  neurasthenia  has 
been  defined  by  Ziemssen  2  as  “a  functional  weakness  of 
the  nervous  system,  varying  from  the  slightest  degrees  in 
simple  localities  to  entire  loss  of  strength  in  the  whole 
nervous  system.”  Arndt  3  states  the  characteristics  of 
neurasthenia  to  be  “  increased  excitability  with  a  ten¬ 
dency  to  rapid  fatigue,  especially  of  the  muscular  sys¬ 
tem.”  He  notes  particularly,  also,  the  cerebral  irrita¬ 
bility,  and  hyperaesthesia  of  the  cranial  nerves,  especially 
those  of  special  senses. 

The  remarkable  experiments  of  Hodge4  are  most  sug¬ 
gestive  as  demonstrating  the  physiological  shrinkage  and 
recovery  of  cell  contents  in  spinal  ganglion  cells  ;  it  is 
shown  that  upon  stimulation  and  upon  normal  exercise, 
the  histological  changes  of  breaking  down  and  building 
up  of  cell  contents  are  accompaniments  of  the  physio¬ 
logical  discharge  and  re-storage  of  energy,  and  as  being 
normally  attendant  upon  fatigue  followed  by  rest. 

The  conditions  of  the  organism  in  normal  and  patho¬ 
logical  fatigue  being  thus  understood,  we  have  a  basis 
for  the  study  of  the  relation  thereto  of  the  mental  symp¬ 
toms  of  fatigue.  It  is  agreed  by  all  observers  that  the 
symptoms  of  nervous  exhaustion  are  mainly  subjective. 
The  objective  symptoms  need  not  be  dwelt  upon  here  ;  the 
commonly  noted  manifestations  of  increased  excitability, 
irritability,  and  restlessness,  are  readily  recognised  as 
representing  the  internal  hyperaesthesia  so  significant  of 
the  “irritable  weakness”  of  nervous  exhaustion.  The 

1  Centralblatt,  f.  Nervenheilkunde,  October,  1890. 

2  Neurasthenia,  Wood’s  Monographs,  Yol.  1,  1889,  p.  534. 

3  Art.,  Neurasthenia,  Tuke’s  Diet.  Psych.,  Med.,  1892,  Yol.  2,  p.  843. 

iAmer.  Jour,  of  Psychol.,  May,  1888  ;  May,  1889  ;  and  February,  1891. 

Also,  Jour,  of  Morphology,  November,  1892. 


8 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


purpose  now  is  to  show  the  significance  of  a  few  easily, 
and  in  fact  commonly,  recognised  subjective  or  mental 
symptoms,  which  stand  as  distinctive  signs  of  fatigue. 
They  furnish  a  ready  index  of  the  fatigue  and  auto¬ 
intoxication  of  nerve  and  muscle  tissues  as  a  guide  for 
diagnosis,  prophylaxis,  and  treatment ;  and  the  general 
symptoms  of  nervous  exhaustion  can  be  understood 
better  and  earlier  by  the  proper  interpretation  of  the 
mental  symptoms. 

3.  SOME  ELEMENTARY  FACTS  OF  THE  NERVOUS  AND 

MENTAL  MECHANISM. 

In  order  to  make  clear  the  changes,  that  we  call  symp¬ 
toms,  in  the  mental  manifestations,  it  is  necessary  to 
note  some  elementary  facts  in  the  relations  between  the 
functions  of  the  mind  and  body.  While  they  are  very 
complex  in  their  detail,  there  are  still  certain  broad  gen¬ 
eralisations  that  we  could  readily  grasp  but  for  the 
difficulty  of  keeping  a  number  of  the  elements  alike 
prominent  in  our  minds  at  the  same  time,  while  studying 
their  inter-play.  This  may  be  aided,  with  some  exercise 
of  the  imagination,  by  the  tabulated  diagram  here  pre¬ 
sented.  It  is  designed  to  represent  the  nervous  and 
mental  mechanism ,  and  to  show  some  of  the  relations  of 
the  inner  activities  that  we  call  mental,  to  the  body  in 
general,  and  to  the  environment. 

Let  us  suppose  that  we  can  look  into  the  region  of  con¬ 
scious  mind  as  into  an  enclosed  place,  and  a  section  being 
made  of  it  we  can  see  noted  thereon,  as  in  the  “  field  of 
consciousness,”  the  modes  of  mental  action  as  they  are 
designated  by  common  agreement.  At  the  other  end  of 
the  diagram  are  noted  the  organs  of  special  sense  through 

« 

which  stimuli  from  the  environment  start  impulses  that 
are  conducted  along  sensory  tracts,  and  produce  physical 
sensations  in  the  sensory  centres  in  the  entrance  to  the 
field  of  consciousness.  When  these  sensations  are  in¬ 
tense  enough  to  pass  over  “the  threshold”  of  the  field  of 


THE  MENIAL  SYMPTOMS  OF  FATIGUE.  9 


NERVOUS  AND  MENTAL  MECHANISM 


10 


TEE  MENTAL  SYMPTOMS  OF  FATIGUE. 


consciousness,  there  is  a  conscious  mental  perception  of 
such  sensations,  as  of  sight,  hearing,  and  the  like.  This 
is  the  initial  event  of  the  process  by  which  we  mentally 
see,  perceive,  and  know,  something  in  the  environment ; 
there  is,  through  sensory  action,  the  presentation  in  our 
field  of  consciousness,  and  the  perception  of  what  we  call 
the  image  or  idea  of  the  external  thing.  But  we  may 
immediately  remember  that  we  have  seen  the  same  object 
before,  and  we  become  conscious  of  an  action  of  memory , 
by  which  we  retain  impressions  previously  received,  and 
can  recall  them  by  the  law  of  association  of  ideas.  We 
image  them  again,  or  imagine  them.  Thus  a  complex 
mode  of  mental  action  arises;  there  is  consciousness ,  then 
conscious  perception  of  a  sensation,  as  from  the  sense 
of  sight,  and  the  memory ,  acting  all  together.  Hard 
upon  this  comes  the  higher  process  of  ideation  or  intel¬ 
lection,  the  comparing  process,  by  which  we  conceive 
abstract  notions  of  things,  judge  them  by  comparison, 
and  reason  about  them.  All  these  may  be  included  also 
in  the  mode  of  consciousness  along  with  perception  and 
memory,  and  form  parts  of  a  complex  process  of  knowing, 
or  intellection,  although  we  name  them  as  separate 
actions.  Whenever  we  talk  with  a  man,  we  gauge  and 
test  minutely  all  these  operations  of  his  mind  with  great 
practical  accuracy.  We  estimate  his  mental  quality  and 
power  ;  we  judge  the  man  by  what  his  mind  can  do. 

One  of  the  points  of  present  interest  is  now  before  us ; 
as  the  antecedent  fact  in  the  mental  process  just  described, 
we  must  premise  the  state  or  existence  of  conscious¬ 
ness,  without  which  there  can  be  no  mental  action.  We 
may  say  that  there  is  latent  consciousness  in  an  unborn 
infant,  that  soon  after  enters  upon  conscious  life  ;  then 
consciousness  springs  into  action,  and  the  first  percep 
tion  is  likely  to  be  of  sensations  from  the  sense  of  touch. 
But  active  consciousness  is  always  attending  to  some 
presentation  in  its  field,  to  the  more  or  less  complete 
exclusion  of  other  presentations.  While  the  multitude 
of  sensations  are  thronging  into  the  sensorium  through 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


11 


all  the  organs  of  special  sense,  the  attention ,  being  fixed 
upon  some  intensified  perception,  excludes  all  but  this 
intensified  one.  The  same  is  true  of  a  presentation  of 
memory,  or  of  a  process  of  reasoning  ;  or  all  these  may 
be  involved  in  a  complex  object  of  attention.  When¬ 
ever,  by  the  action  of  what  we  call  the  attention,  we  hold 
in  mind  a  perception,  a  memory,  or  the  data  of  a  process 
of  reasoning,  we  are  exercising  the  memory  also  in  the 
very  act  of  retaining  all  these  elements  of  the  mental 
process^  On  the  other  hand  we  know  that  by  the  atten¬ 
tion  we  can  control  the  memory,  by  controlling  and 
changing  the  flow  of  ideas  it  recalls ;  and  all  this 
goes  to  show  the  inseparable  working  together  of  these 
processes. 

The  attention  is  a  mental  element  of  the  greatest 
interest,  and  is  commonly  regarded  as  meaning  a  “con¬ 
centration  of  consciousness.  ’  ’  According  to  Sully1  it  may 
be  defined  as  the  active  intensification  of  consciousness 
in  particular  directions.  Whatever,  at  any  time, 
“occupies  the  mind,”  is  for  the  moment  the  supreme 
object  of  attention.  The  attention  is  one  with  active 
consciousness,  and  is  often  described  as  accompanying 
every  other  mental  action. 

It  is  a  common  experience,  in  revery  and  in  dreams, 
that  a  spontaneous  flow  of  ideas  is  continually  passing 
through  the  mind  ;  one  item  follows  another  in  the 
train  of  associated  ideas  through  the  working  of  memory 
and  imagination  by  the  laws  of  habit  and  association, 
without  direction  or  control.  The  attention  is  then  said 
to  be  acting  in  one  of  its  two  forms,  and  this  form  is 
spontaneous  attention.  It  is  also  called  reflex  attention , 
as  it  acts  by  being  attracted  to  the  idea  or  object  in  the 
mind  that  most  interests  it,  or  keeps  it  on  the  alert,  or 
stimulates  it.  The  idea  may  be  intensified  in  interest 
by  pleasurable  or  painful  feeling ,  by  a  desire  or  a  fear. 
The  act  itself  of  attention  to  such  an  object  of  thought, 
increases  the  intensification  of  it,  and  tends  to  keep 

1  Art.,  Attention.  Tuke’s  Diet.  Psych.  Med.,  Yol.  1,  p.  106. 


12  TEE  MENTAL  SYMPTOMS  OF  FATIGUE. 

ideas  of  kindred  nature  in  the  mind  ;  the  mind  dwells 
upon  them,  is  absorbed  in  them. 

Voluntary  attention  is  the  other  form  of  this  mental 
function  ;  and  this  is  at  the  very  centre  of  interest  in 
this  inquiry,  ft  is  spontaneous  attention  with  the  added 
power  of  direction  and  control  ;  the  attention  is  thus  in¬ 
separably  associated  with  the  will,  volition,  or  control¬ 
ling  power.  The  essential  fact  is  that  in  voluntary  atten¬ 
tion  lies  the  mental  activity  of  inhibition  ;  it  is  inhibition 
working  through  attention.  According  to  Foster,  just 
as  physiological  inhibition  plays  its  part  in  the  lower 
mechanisms  of  the  body,  so  is  it  important  in  the  whole 
work  of  the  central  nervous  system.  Also,  just  as  all 
voluntary  muscular  actions  are  under  the  control  of  an 
attending  will,  so  is  the  directing  and  concentrating  of 
the  attention  upon  a  chosen  thought  an  act  of  volition. 
A  man  controls  his  own  mind  by  willing  his  attention, 
as  it  were,  to  be  fixed  upon  some  one  item  or  object,  in 
the  train  of  presented  ideas,  to  the  exclusion  of  others. 
He  thinks  about  what  he  chooses  to  think  about,  and 
inhibits  mind  wandering.  He  may  make  the  most 
worthy  object  interesting*^  this  is  intensified  by  holding 
in  mental  view  its  worthiness,  and  thus  the  attractions 
of  less  worthy  interests  and  emotions  are  resisted. 

Sully  says  it  is  pre-eminently  by  acts  of  attention  that 
all  the  elaborative  work  of  thought  is  effected,  and  that 
the  attention  is^  the  great  conditioning  factor  in  our  intel¬ 
lectual  life  ;  all  great  intellectual  achievement  involves 
energy  of  will  acting  as  voluntary  attention.  The  student 
attains  to  this  power  by  training  and  education  of  his 
higher  mental  control ;  the  man  who  chooses  the  path  of 
wisdom  and  rectitude  exercises  and  strengthens  his 
power  of  voluntary  attention  by  the  practice  of  self-con¬ 
trol  in  inhibiting  the  impulses  of  his  passions?  Thus  it 
is  that  voluntary  attention  is  in  close  relation  with  the 
highest  as  well  as  the  latest  developed  acquirements  of 
the  mind,  in  its  power  to  use  the  force  of  nervous  energy 
to  the  best  effect.  It  is  well  known  that  the  latest 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


13 


acquirements  are  soonest  impaired  with  the  abatement 
of  normal  energy. 

Every  exercise  of  the  will  in  attention  is  accompanied 
by  the  expenditure  of  energy,  and  by  the  “  sense  of 
effort  ’’that  occurs,  particularly  when  the  attention  works 
against  some  resisting  motive,  interest  or  feeling.  This 
directing  and  inhibitory  control  is  at  its  best  in  the  equi¬ 
librium  of  health  of  mind  and  body,  and  therefore  it  is  a 
most  important  means  of  estimating  mental  health  and 
vigor ;  mental  disorder  is  commonly  attended  with  dis¬ 
turbances  of  the  normal  process  of  attention,  as  will 
directly  appear  in  the  discussion  of  mental  symptoms. 
This  constitutes  one  of  the  points  of  great  diagnostic 
value. 

We  have,  so  far,  concerned  ourselves  in  this  discussion 
quite  exclusively  with  the  processes  of  knowing  or  intel¬ 
lection.  But  we  are  always  conscious  of  another  order  of 
mental  phenomena,  the  feelings ,  and  they  are  of  pleas¬ 
ure  or  of  pain,  or  they  may  be  in  varying  degrees  agree¬ 
able  or  disagreeable.  From  the  lower  forms  of  bodily 
pleasure  and  pain,  upward  in  the  scale  to  those  aroused 
by  the  perceptions  of  color  and  music,  the  feelings  are 
said  to  be  “  corporeal.”  But  the  purely  mental  feeling 
that  always  attends  upon  pleasurable  or  painful  ideas,  is 
inseparable  from  them.  Without  ideas  there  can  be  no 
such  feeling  ;  and  according  to  its  intensity,  a  feeling  of 
pleasure  or  pain  intensifies  the  idea  it  accompanies,  and 
makes  it  prominent  in  consciousness,  tending  to  attract 
more  strongly,  and  to  hold,  the  attention.  Thus,  as  has 
already  been  shown,  there  may  be  an  antagonism  between 
worthy  and  unworthy  ideas  and  feelings,  or  in  the  moral 
sense  of  right  and  wrong,  with  need  of  the  inhibitory 
power  of  voluntary  attention  to  choose,  control,  and 
guide  conduct.  This  brings  out  the  opposing  factors  in 
the  operation  of  will,  attention,  ideas,  and  feelings.  The 
feelings  excited  by  ideas  prompt  to  action,  which  may 
be  inhibited  or  augmented  by  an  opposing  or  consenting 
will. 


14  tiie  mental  symptoms  of  fatigue. 

Referring  now  to  the  diagram,  the  relations  of  these 
activities  are  seen  to  be  noted  in  their  natural  order. 
Feeling  follows  upon  intellection,  and  all  the  included 
mental  activities  are  operating  in  the  field  of  conscious¬ 
ness.  The  outcome  of  this  interplay  is  in  the  union  of 
willing  with  acting  at  the  point  where  the  resultant  of 
the  mental  forces  appears  to  act  upon  the  motor  centres, 
or  stimulate  in  them  the  impulses  that  end  in  the  setting 
free  of  muscular  motion.  Thus  the  picture  of  the  “  nerv¬ 
ous  circle  ’ 5  is  now  complete,  and  shows  the  working  of 
the  nervous  and  mental  mechanism  under  the  stimula¬ 
tion  of  sensations  through  the  special  senses.  Then  con¬ 
sciousness,  through  the  attention  (these  two  being  gen¬ 
eral  states,  or  modes  of  mental  action),  knows,  or  “sees  ” 
in  the  very  mind’ s  eye,  the  special  modes  of  action  which 
we  call  sense-perception,  memory,  reasoning,  feeling,  and 
the  willing  of  motor  impulses  which  end  in  muscular 
motion.  This  completes  the  “  circle.” 

The  sensations  from  the  special  senses  are  those  of 
which  we  are  most  conscious;  they  are  of  high  intensity, 
but  we  little  realise  that  they  are  small  in  volume  com¬ 
pared  with  the  great  inflow  of  organic  sensations  of 
which,  in  normal  conditions,  we  are  not  conscious. 
These  organic  sensations,  that,  according  to  Ribot,  give 
us  the  sense  of  body ,  or  of  personality ,  are  of  low  inten¬ 
sity  but  vast  in  volume  ;  proceeding  from  every  minute 
part  of  the  tissues  and  organs  of  the  body,  their  inflow, 
along  sensory  tracts,  enters  the  sensorium  beneath  the 
“threshold  of  consciousness”  into  the  region  of  sub- 
consciousness.  Their  origin  is  shown  in  the  sources 
noted  in  the  fainter  letters  in  the  diagram,  and  their 
course  by  the  dotted  lines.  The  muscular  sense,  which 
is  complex  in  its  origin,  includes  feelings  that  afford  an 
example  of  the  more  pronounced  of  these  organic  sensa¬ 
tions.  Thus,  we  get  the  sense  of  weight  and  posture. 
Again  there  are  those  not  felt  in  normal  conditions, 
but,  like  hunger  and  thirst,  which  are  general  in  their 
origin,  may  become  intensified  so  that  at  times  there  is 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


15 


consciousness  of  tliem.  There  are  still  others,  as  in  the 
morbid  conditions  of  hyperaesthesia,  and  paraesthesia, 
that  appear  as  pain  or  a  general  feeling  of  misery  ;  they 
are  vague  in  character,  and  their  sources  often  can  not 
be  determined. 

These  organic  sensations,  and  their  alterations,  are  of 
such  a  nature  that  they  afford  another  point  in  the  nerv¬ 
ous  and  mental  mechanism  of  great  diagnostic  value.  In 
normal  states,  when  all  is  well  with  the  organism  in  the 
equilibrium  of  health,  they  constitute  the  sense  of  well¬ 
being.  Here  again  we  have  an  important  means  of  meas¬ 
uring  any  falling  olf  of  nervous  vigor  ;  from  the  slighter 
alterations  of  bodily  feelings  in  fatigue  to  those  that 
create  a  persistent  sense  of  ill-being,  these  changes  cause 
variations  in  the  ‘ £  emotional  tone  ’  ’  that  are  the  most 
sensitive  indices  of  the  degree  of  fatigue  and  exhaustion, 
both  normal  and  pathological.  The  emotional  tone  is 
thus  seen  to  be  affected  in  two  ways.  There  may  be,  in 
health,  all  degrees  of  pleasurable  or  painful  mental  feel¬ 
ing,  between  the  extremes  of  exaltation  and  depression, 
according  to  what  one  has  to  think  about ;  in  this  case  a 
lowered  emotional  tone  from  grief  or  care  may  be  a  pass¬ 
ing  event,  or  if  prolonged,  may  have  a  directly  debilitat¬ 
ing  effect  upon  the  organism  through  the  motor  tract 
of  the  nervous  system.  The  stimulant  and  dejnessant 
effects  of  the  natural  emotions  upon  the  circulatory  sys¬ 
tem  and  upon  bodily  health  in  general,  are  well  enough 
known.  On  the  other  hand,  a  persistent  state  of  morbid 
dejuession  of  feeling  may  be  no  more  than  the  mental 
concomitant  of  bodily  ill-being,  however  it  may  have 
been  induced.  There  may  be  three  events  in  the  train  : 
first,  undue  care,  real  trouble,  and  anxiety  or  grief  may 
initiate  a  general  condition  of  ill-being,  which,  in  turn, 
may  be  the  cause  of  morbid  depression  as  the  third 
event.  The  first  in  this  order  may  be  entirely  wanting, 
but  the  condition  of  ill-being,  through  impairment  of 
health  and  nervous  vigor,  must  exist  from  some  cause 
before  the  strictly  morbid  mental  symptoms  can  appear. 


16 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


4.  THE  ALTERATIONS  OF  MENTAL  FUNCTIONS  THAT  ARE 

SIGNIFICANT  AS  SYMPTOMS. 

It  now  remains  to  describe  the  special  alterations  in 
some  of  these  prominent  factors  of  the  mental  mechan¬ 
ism,  and  their  significance  in  conditions  of  normal  and 
pathological  fatigue.  In  normal  fatigue  it  is  to  be 
kept  in  mind,  that  the  dual  physical  condition  is  one 
of  the  expenditure  of  nervous  energy  in  work  to  the 
immediate  fatigue  of  nerve  cells,  and  the  accumulation, 
locally  and  in  the  circulatory  system,  of  toxic  waste 
products  ;  and  that  the  processes  of  nutrition  and  elim¬ 
ination  require  time  and  rest.  The  mental  concomitants 
of  this  condition  are :  a  diminished  sense  of  well- 
being^  or  a  feeling  of  fatigue,  sometimes  amounting  to 
a  sense  of  ill-being ,  which  includes  in  its  complex  causa¬ 
tion  the  influence  of  the  toxic  elements.  The  emotional 
tone  is  lowered,  and  there  is  less  vivacity  of  feeling.  There 
is  also  lessened  mental  activity  in  general.  Voluntary 
attention  is  fatigued ;  that  is,  the  mental  inhibition  is 
lessened,  with  diminished  control  over  the  attention,  and 
one  is  conscious  of  an  extra  sense  of  effort  in  mental 
work.  There  is  “mind  wandering.”  The  logical  pro¬ 
cesses  work  more  slowly  and  with  less  effect  in  making 
comparisons  and  judgments,  and  in  reasoning  to  conclu¬ 
sions  ;  the  tired  attention  holds  on  with  effort  to  one 
member  of  a  proposition,  while  another  slips  away^ 
There  is  a  consciousness  of  mental  inadequacy  and  diffi¬ 
culty  in  keeping  awake.  This  is  the  common  experience 
of  evening  tire.  Restoration  follows  upon  a  due  amount 
of  rest,  sleep  and  nutrition,  and  the  somnolence  disap¬ 
pears  when  the  acid  waste  products,  etc.,  in  the  circula¬ 
tion  are  removed. 

The  condition  of  pathological  fatigue  is  induced 
when  the  process  of  restoration  is  continuously  incom¬ 
plete.  Then  we  have  to  conceive  of  deficient  nutrition 
and  an  irritating  intoxication  as  both  contributing  to  the 
“  irritable  weakness,”  which  is  a  manifestation  of  the 
characteristic  hyperaesthesia.  We  may  now  note  the 


TEE  MENTAL  SYMPTOMS  OF  FATIGUE. 


17 


significant  alterations  of  the  feelings,  the  irritability  of 
temper,  the  weakening  of  the  power  of  voluntary  atten¬ 
tion,  and  the  effects  of  these  alterations.  The  patient 
may  complain  of  painful  or  miserable  bodily  sensations, 
hyperaesthesia  and  restlessness  ;  and  often  of  paraes- 
thesia  in  various  forms.  The  symptoms  may  be  ana¬ 
lysed  and  classified  according  to  the  order  of  their 
appearance,  and  the  functions  affected. 

The  first  order  of  mental  symptoms  of  pathological 
fatigue,  in  the  importance  and  earliness  of  their  appear¬ 
ance,  may  now  be  noted.  These  most  obvious  mental 
signs  are  the  characteristic  depression  of  feeling ,  a  low¬ 
ering  of  the  emotional  tone ,  and  a  sense  of  ill-being. 

The  symptoms  quickly  reflect  debilitated  bodily  con¬ 
ditions  that  are  the  sources  of  the  “  miserable  feelings.” 
These  subjective  indications  are  often  the  only  ones  of 
the  existing  exhaustion  in  its  complex  character.  Again, 
they  are  corroborative  of  a  suspicion  of  general  neuras¬ 
thenia  when  complaint  is  made  of  some  local  functional 
disorder  ;  in  other  words,  local  disorder  is  often  shown  to 
be  simply  an  expression  of  general  neurasthenia,  of  which 
the  only  diagnostic  evidence  is  in  the  mental  symptoms. 

The  second  order  of  mental  symptoms,  in  time  of 
appearance,  is  usually  the  persistent  decrease  of  the 
power  of  voluntary  attention  ( reflex  attention ),  and 
sometimes  of  memory ;  there  is  also  the  sense  of  in¬ 
adequacy  of  effort. 

These  symptoms  refer  to  the  attention,  which  acts  in  a 
more  spontaneous  and  reflex  manner  as  its  control  is 
weakened ;  the  memory  is  weakened  in  its  power  of 
retaining  and  recalling  ideas.  This  lessening  of  inhibi¬ 
tory  power,  and  mental  activity  in  general,  shows  the 
abatement  of  cerebral  energy.  It  does  not  always  appear 
to  the  observer,  for  the  reason  that  the  patient  may  draw 
upon  the  reserved  nervous  energy,  and  put  forth  more 
effort  in  the  act  of  controlling  his  attention,  and  succeed 
in  doing  it.  But  he  is  both  expending  energy  more 
rapidly  in  so  doing,  and  is  conscious  of  the  need  of 


18  THE  MENTAL  SYMPTOMS  OF  FATIGUE. 

increased  effort ;  lie  will  usually  readily  confess  it  on 
being  questioned.  This  consciousness  finally  amounts 
to  the  very  characteristic  sense  of  inadequacy.  This 
symptom  of  weakened  voluntary  attention  is  also  an 
early  one,  and  is  very  diagnostic.  The  patient  will  often 
complain  that  he  cannot  keep  his  thoughts  on  his  work 
or  business,  or  has  to  read  over  again  what  he  reads,  and 
can  not  remember  it.  One  patient  said  1  ‘  I  can  not  sense 
it;”  and  another,  “I  can  not  center  my  mind  on  what  I 
try  to  do.” 

A  third  order  of  symptoms  may  now  arise,  and  it  is  an 
interesting  fact  that  they  grow  out  of  the  other  two 
orders,  and  are  their  logical  consequence ;  these  are 
morbid  introspection,  retrospection,  and  apprehension 
{worry  and  hypochondria). 

These  symptoms,  when  manifestly  developed,  mark  a 
graver  degree  of  fatigue.  The  emotional  tone  being  low¬ 
ered,  the  patient  in  a  state  of  depression  of  feeling  is 
prone  to  “look  upon  the  dark  side  of  things.”  Ideas 
are  intensified  that  are  accompanied  by  painful  feelings, 
which  are  thus  in  harmony  with  the  prevailing  emotional 
tone.  There  being  also  a  lessening  of  nervous  energy  in 
voluntary  attention,  it  cannot  inhibit  the  intensified 
painful  ideas  and  feelings,  and  there  is  consequently 
worry  about  the  present,  past,  and  future.  The  vague 
fear  arises  of  being  unable  to  meet  the  requirements  of 
the  future.  The  increasing  sense  of  present  inability 
gives  intensification  to  the  characteristic  sense  of  inade¬ 
quacy  noted  by  Beard  as  being  so  prominent. 

There  is  one  other  set  of  symptoms  to  be  mentioned  as 
constituting  a  fourth  order.  While  those  previously 
noted  are  purely  mental,  these  are  partly  so,  but  relate 
chiefly  to  alterations  that  cause  peculiar  bodily  effects, 
and  are  often  manifest  to  the  observer.  These  symptoms 
are  :  changed  organic  sensations,  physical  and  mental 
irritability,  and  restlessness ;  diminished  sensitive¬ 
ness,  dullness  and  languor. 

There  is  apparent  irregularity  in  these  changes  of 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


19 


bodily  feelings  and  their  manifestations — the  intensify¬ 
ing  of  some  and  the  lessening  of  others.  Arndt1  says  : 
u  It  is  clear  that  the  increased  hyperaesthesia,  which  a 
degenerating  nerve  at  first  presents,  can  not  last  long, 
and  that  soon  decreased  excitability,  blnntness,  paresis, 
or  whatever  we  call  fatigue  or  exhaustion,  must  take  its 
place.” 

There  is  not  alone  hyperaesthesia,  with  the  external 
signs  of  irritability  and  restlessness,  but  there  is  much 
diminished  sensitiveness.  Some  cases  are  altogether  of 
the  latter  character,  and  many  present  both  conditions 
at  the  same  time,  in  some  particulars.  It  may  be  a  ques¬ 
tion  of  the  different  effects  of  variations  in  the  toxic 
waste  products.  While  chemical  physiology  and  pathol¬ 
ogy  do  not  yet  enable  us  to  ascribe  sensory  and  motor 
disorders  definitely  to  the  influence  of  poisons  produced 
within  the  organism  by  its  own  activity,  it  cannot  be 
doubted  that  both  the  conditions  of  nervous  irritability 
and  those  of  dullness,  languor,  and  stupor,  may  be  so 
caused.  It  is  certain  that  such  external  manifestations 
may  be  caused  as  the  direct  expression  of  defective 
functional  activity  in  cerebral  centres  that  are  the  source 
of  the  nervous  energy  which  innervates  and  controls 
both  the  somatic  and  mental  mechanisms.  The  study 
of  physical  expression  which  Darwin  raised  to  the  dig¬ 
nity  of  a  new  science,  shows  that  while  there  is  certain 
voluntary  control  over  it,  still  the  manifestations  in  the 
muscular  movements  of  expression,  whether  occurring 
in  the  face  or  the  extremities,  have  a  direct  automatic 
dependence  upon  interior  states  of  the  central  nervous 
system,  which  are  thus  externally  reflected.  The  inflow 
of  organic  sensations  to  the  senorium  has  its  complement 
in  the  constant,  regular  and  subconscious  transmission 
of  nerve  force  from  central  cells  to  the  muscular  peri¬ 
phery.  This  accords  with  Gowers’  statement  that  every 
structure  of  the  brain  concerned  with  sensation  proper  is 
connected  directly  or  indirectly  with  a  part  concerned 

1  Loc.  cit. 


20  the  mental  symptoms  of  fatigue. 

with  motion  ;  and,  in  regard  to  the  unstable  condition  of 
brain  cells  in  disease,  when  the  equilibrium  between  the 
discharge  of  energy  and  the  inhibition  of  it  is  disordered, 
“the  discharge  may  depend  on  the  production  of  force 
within  being  increased  in  excess  of  the  resistance,  or  on 
the  resistance  being  duly  lessened.” 

In  the  common  forms  of  insanity  are  seen  the  most 
pronounced  expressions  of  excessive  or  diminished  cen¬ 
tral  activity,  and  this  applies  alike  to  innervation  and 
inhibition,  whether  mental  or  somatic.  In  the  belief  of 
the  writer1  it  is  possible  to  detect  important  variations  in 
the  several  elements  of  mental  activity  in  normal  fatigue 
and  nervous  exhaustion.  For  example  :  the  letting  down 
of  mental  power  in  voluntary  control,  with  the  conse¬ 
quent  lessened  inhibition  of  verbal  expression  of  grief 
and  worry,  or  excitability  and  aggressiveness.  Bancroft2 
has  made  an  instructive  application  of  the  physiological 
principles  of  expression,  to  the  study  of  facial  expression 
of  the  emotions  in  insanity  and  of  expression  in  posture, 
etc.,  as  the  results  of  habit  in  automatic  muscular  action. 
His  work  gives  definite  value  to  the  clinical  use  of  photog 
raphy  in  the  physical  expression  of  mental  changes. 

All  such  clinical  studies  of  mental  symptoms  demon¬ 
strate  the  value  of  precise  appreciation  of  the  changes 
in  the  elementary  mental  activities.  It  is  common  to 
observe,  in  mania,  either  excessive,  uninhibited,  mental 
and  motor  activity,  or  the  quite  normal  control  of  the 
latter,  along  with  the  gravest  deficiency  of  mental  inhi¬ 
bition.  Again,  there  is  excessive  nerve-muscular  activity, 
or  tension  in  fixed  attitudes,  in  the  mental  and  motor 
expression  of  painful  emotion  in  melancholia,  and  in 
consequence  of  lessened  inhibitory  will  power  ;  and  still 
again,  all  expression  may  be  abolished  in  the  real  mental 
stupor  of  melancholia  and  mania.  This  abolition  may 

1  Pathological  Fatigue  or  Neurasthenia;  also  the  Shattuck  lecture;  1891 
Med.  Com.  Mass.  Med.  Soc. — Amer.  Jour.  Insanity,  July  and  Oct.,  1891. 

2Automatic  muscular  movements  among  the  insane,  Amer.  Jour,  of 
Psych.,  Feb.,  1891. 


THE  MENTAL  SYMPTOMS  OF  FATIGUE.  21 

also  be  due  alone  to  the  fact  that,  while  perception  and 
ideation  are  quite  normal,  the  power  to  give  expression 
to  them  is  diminished  or  lost,  either  in  the  failure  of  the 
mental  function  of  willing,  or  of  excitability  in  the 
motor  centres.  A  man  at  the  McLean  Hospital,  who  was 
apparently  in  profound  stupor,  afterwards  said :  “  I 
wanted  to  answer  you,  but  couldn’t  make  my  jaws  go.” 
A  woman  who  would  stand  in  a  fixed  position  for  hours 
with  almost  entire  loss  of  muscular  movement  and  ex¬ 
pressionless  face,  could  respond  to  kind  words  only  by 
directing  her  eyes,  and  they  would  fill  with  tears.  When 
she  was  well,  the  next  year,  she  gratefully  told  what 
had  been  said  and  done  to  her.  The  apparent  stupor  is 
often  mistaken  for  the  real  condition. 

These  discriminations  of  the  mental  processes  being 
once  established,  they  have  the  highest  therapeutic  value 
in  their  preventive  application.  Hence  the  thesis  of 
this  paper :  the  importance  of  an  early  appreciation  of 
the  mental  symptoms  of  normal  fatigue  that  tends  to 
nervous  exhaustion,  for  they  are  prodromic  of  its  graver 
forms.  Moreover,  the  recognition  of  the  significance  of 
changes  in  the  motor  and  sensory  manifestations,  in  the 
direction  of  languor  as  well  as  irritability —  anaesthesia 
as  well  as  hyperaesthesia  —  is  of  the  first  importance  in 
the  difficult  task  of  managing  convalescence  from  true 
neurasthenia.  The  u  irritable  weakness,”  includes  the 
liability  to  quick  exhaustion  of  the  small  increments  of 
nervous  energy  that  have  been  slowly  gained,  and  there¬ 
with  the  speedy  reduction  of  sensory,  as  well  as  motor 
power,  to  the  degree  of  “  bluntness,”  as  Arndt  has  stated 
it.  Pathological  fatigue,  or  nervous  exhaustion,  being 
shown  to  be  a  condition  in  which  there  is  direct  and 
constant  relation  between  physical  disorder  and  mental 
symptoms,  these  should  be  noted,  together  with  both  the 
increase  and  the  blunting  of  sensitiveness,  in  any  compre¬ 
hensive  definition  of  the  disease.  It  may  therefore  be 
defined  as  follows  :  Neurasthenia  is  a  morbid  condition 
of  the  nervous  system ,  and  its  underlying  characteris- 


22 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


tics  are  excessive  weakness ,  and  irritability  or  languor , 
with  mental  depression  and  weakened  attention. 

This  method  of  analysis  into  four  orders  of  symptoms 
is  applicable  to  all  cases  of  neurasthenic  disorder  of  the 
physiological  activities  involved,  from  the  passing  over 
of  normal  into  pathological  fatigue,  in  the  simplest 
forms,  to  the  gravest  manifestations  of  emotional  dis¬ 
turbances,  disordered  attention,  and  sensory  and  motor 
irritability  and  languor.  The  symptoms  included  in  the 
first  three  orders  are  regarded  as  purely  mental ;  those 
characterised  in  the  fourth  order,  while  referring  to  the 
well-marked  development  of  changes  in  sensitiveness 
and  activity  of  bodily  functions,  imply  the  necessary 
association  with  them  of  the  mental  symptoms  before 
noted.  These  changes  of  bodily  sense  and  activity  may 
be  detected,  in  the  slighter  degrees,  in  the  earlier  stages 
of  neurasthenia.  The  value  of  the  practical  application 
of  these  discriminations  in  diagnosis  may  now  be  illus¬ 
trated  by  describing  some  of  the  special  ways  in  which 
certain  symptoms  must  be  interpreted.  By  this  method 
of  analysis  we  may  readily  estimate  the  significance  of 
the  symptoms  of  depression  of  feeling,  of  weakening  of 
voluntary  attention,  and  of  worry.  But  there  are  certain 
more  subtle  effects  of  the  mixed  condition,  usually  found, 
of  hyperaesthesia  and  anaesthesia. 

One  of  the  most  striking  special  symptoms  which  the 
foregoing  considerations  point  out  and  may  serve  to  ex¬ 
plain,  is  a  paradoxical  one,  but  one  most  commonly  pre¬ 
sented  for  clinical  observation.  The  sensory  function  by 
which  the  complex  normal  feelings  of  fatigue  are 
appreciated,  may  itself  be  over-exercised  to  exhaustion. 
(There  is  tire  of  the  power  to  feel  the  tire.  This  condi¬ 
tion  may  be  called  fatigue-anaesthesia ,  and,  beginning 
with  the  early  stages  of  pathological  fatigue,  there  is 
usually  some  degree  of  it.  Every  physician  has  ex¬ 
perienced  this  when,  after  a  night  of  anxious  profes¬ 
sional  work,  ,with  loss  of  sleep,  he  has  a  day  of  excit¬ 
able  alertness  of  mind  and  body,  and  there  is  a  sense  of 


TEE  MENTAL  SYMPTOMS  OF  FATIGUE.  23 

nervous  strain,  with,  perhaps,  undue  mental  facility  and 
physical  irritability.  Many  hours  sleep  may  be  gained 
in  the  following  night,  but  instead  of  feeling  refreshed 
he  has  a  sense  of  malaise ,  languor  and  fatigue.  The 
real  fatigue  was  greater  the  day  before,  but  he  could  not 
feel  it  as  such.  It  is  not  until  the  second  day  after  the 
excessive  effort  that  he  has  recovered  his  exhausted 
power  to  feel  the  fatigue.  In  a  lesser  degree  this  fatigue- 
anaesthesia  becomes  a  constant  accompaniment  of  the 
neurasthenic  condition.  Over-worked  women,  profes¬ 
sional  and  business  men,  “  work  on  their  nerves,”  and 
say  they  “  don’t  feel  tired,  and  nothing  is  the  matter.” 
They  “ feel  better”  when  actively  exercised  in  their 
customary  labors.  This  condition  comes  on  insidiously 
and  is  a  most  dangerous  onej  The  patient  is  neuras¬ 
thenic  before  anybody  suspects  it.  With  the  impair¬ 
ment  of  the  natural  fatigue-sense  the  mental  effect  is  that 
he  will  not  believe  even  his  physician’s  diagnosis  of 
“fatigue.”  He  is,  therefore,  prone  to  look  for  some 
other  reason  for  his  sense  of  ill-being  and  inefficiency  ; 
and  finds,  in  retrospection,  cause  for  self-reproach  and 
hopelessness  in  the  future. 

Fatigue  -  anaesthesia  manifests  itself  in  connection 
with  another  special  symptom  peculiar  to  conditions  of 
“fatigue,”  that  of  “morning  tire,”  sometimes  called 
“morning  misery.”  Extreme  examples  of  this  are  seen 
in  the  victims  of  dissipation.  In  ordinary  cases  of 
pathological  fatigue  it  is  a  persistent  symptom;  the 
patient  is  likely  to  awake  in  the  early  morning  unre¬ 
freshed  by  a  fair  amount  of  sleep,  and  often  in  the  depths 
of  depression.  The  physical  signs  of  exhaustion  are  then 
more  manifest.  These  symptoms  represent  the  truth  as 
to  his  neurasthenic  condition.  After  breakfast  he  feels 
better,  and  by  the  middle  of  the  day  the  stimulation  of 
the  daily  interests  and  press  of  business  has  apparently 
restored  his  good  feeling.  At  the  close  of  the  day  he  is 
comfortable  and  cheerful,  laughs  at  his  morning  fears, 
and  is  prone  to  over-do  himself  in  recreation  or  evening 
work.  That  day’s  experience  is  regularly  repeated. 


24 


TEE  MENTAL  SYMPTOMS  OF  FATIGUE. 


Each  night  he  rests  enough  to  recover  some  of  the  feel¬ 
ings  that  attend  upon  “  fatigue,”  but  he  often  does  not 
recognise  it  in  the  absence  of  the  true  fatigue-sense.  A 
still  further  blunting  of  this  sense  is  caused  by  the  ill- 
timed  stimulation  of  unwisely  continued  effort.  Along 
with  the  restlessness  of  his  “  irritable  weakness,”  there 
is  a  fictitious  sense  of  well-being  because  of  the  tempor¬ 
ary  abolition  of  the  sense  of  ill-being,  as  in  mild  intoxi¬ 
cation  by  alcohol. 

In  the  management  of  convalescence  from  neurasthenia, 
or  of  cases  that  would  get  well  if  they  could  be  man¬ 
aged,  there  is  nothing  more  discouraging  than  the  succes¬ 
sion  of  relapses  that  they  undergo.  Such  patients,  having 
been  subjected  to  rest  treatment,  may  be  fat  enough  and 
maintain  a  fair  degree  of  comfort  when  effort  is  kept 
within  the  limits  of  pathological  fatigue.  They  complain 
of  tire  and  various  discomforts  upon  a  little  effort,  which 
must  be  made  in  order  to  gain  by  physiological  use  the 
strength  to  make  it.  It  seems  a  never-ending  process 
some  patients  cannot  abide  its  slowness,  and  make  effort 
too  soon  ;  others  resist  great  persuasion  to  make  enough. 
But  some  event  may  occur  that  excites  desire  or  a  sense 
of  duty.  The  undue  quickness  of  response  to  the  stimu¬ 
lation  of  interest  and  attention  is  to  be  recognised  as  an 
evidence  of  irritable  weakness.  The  apparent  ease  and 
unwonted  zest  of  the  effort  is  not  a  manifestation  of  real 
power ;  it  means  that  there  is  a  speedy  blunting  of  the 
sense  of  fatigue.  The  reaction  of  exhaustion  and  mental 
misery  that  follows  shows  the  real  weakness  and  the  need 
of  unfailing  patience  and  discretion.  Most  patients  of 
this  class  have  to  be  taught  how  to  recognise  the  mental 
and  physical  signs  of  fatigue  peculiar  to  themselves, 
other  than  the  normal  feeling  of  it.  They  must  also  be 
taught  that  some  degree  of  fatigue  thus  manifested  must 
be  regularly  incurred  as  wholesome  tire.  But  both 
patient  and  physician  must  be  guided  alone  by  indi¬ 
vidual  experience  and  judgment  as  to  the  amount  of 
effort.  Feeling  is  often  a  misleading  guide  for  doing  or 
not  doing. 


THE  MENTAL  SYMPTOMS  OF  FATIGUE. 


25 


Many  neurasthenic  people  are  plied  with  recreation 
to  “  distract  the  attention,”  and  go  on  journeys  in 
search  of  health,  when  it  is  not  stimulation,  mental  or 
physical,  that  is  needed,  but  rest.  The  physician  may 
save  many  a  patient  from  such  a  final  strain,  that  would 
precipitate  a  break-down,  by  recognising  the  fact  that 
his  apparent  ability  to  do  things  without  fatigue,  when 
the  mental  signs  of  it  are  present,  is  the  strongest  indi¬ 
cation  that  he  has  reached  a  dangerous  degree  of  nervous 
exhaustion,  marked  so  plainly  by  loss  of  the  fatigue-sense. 
In  such  cases,  after  a  course  of  rest  treatment,  which 
must  often  be  more  or  less  modified,  exercise  becomes 
most  important,  in  the  form  of  gentle  bodily  effort  and 
mental  stimulation  by  recreation  in  gradually  increased 
amount.  The  guide  to  the  limitation  of  exercise  is  to  be 
found  in  its  effects,  such  as  the  slight  return  of  restless¬ 
ness  and  insomnia  at  night,  and  the  mental  and  bodily 
discomfort  liable  to  appear  on  the  following  morning. 
Exercise  may  be  pressed  to  the  extent  of  not  causing 
these  effects  ;  it  promotes  nutrition,  and  excretion  of 
waste  products,  the  free  action  of  the  skin,  etc. 

The  physician  will  look  to  the  therapeutics  of  tonics 
and  nutrition,  with  careful  attention  to  all  the  forms  of 
elimination.  But  while  he  is  doing  this,  the  successful 
treatment  of  neurasthenia  means  the  careful  recognition 
of  all  its  signs.  The  earliest  indications  for  diagnosis, 
and  the  clearest  for  treatment — and  often  the  only  ones 
— are  the  mental  symptoms.  It  is  the  conditions  of 
fatigue  that  are  to  be  treated,  and  the  study  of  the 
working  of  the  fatigue- sense  affords  the  safest  and  surest 
guide,  although  its  signs  are  so  often  negative.  A  cor¬ 
rect  and  fine  appreciation  of  what  the  mind  can  do 
enters  into  our  commonest  knowledge  and  experience, 
and  we  use  the  most  familiar  words  to  describe  its  oper¬ 
ations.  This  paper  has  been  written  with  the  hope  that 
it  may  be  a  help  to  the  systematic  observation  of  some  of 
the  commonest  and  most  valuable  of  clinical  indications, 
both  for  prevention  and  cure. 


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